This invention relates to hand held rotary power saws commonly referred to as circular saws or skill saws and in particular to an adaptor to such saws which position a saw blade beyond a fixed guard rail on the saw, so as to allow the blade to be positioned close to a wall surface in parallel relation thereto.
In the past, power saws could not be used to make cuts close to a wall surface because of the fixed guard rail. Practically all power saws have a fixed guard rail which surrounds the cutting edge of the rotating blade to prevent accidents. The guard rail has a flat table surface which slides over the surface of the object to be cut and is adjustable to limit the depth of cut of the blade.
While the guard rail surrounds the dangerous cutting edge of the blade it also prevents close cuts next to a wall surface. The closest cut is at least the distance from the blade to the side edge of the guard rail. Even the adaptor of U.S. Pat. No. 3,371,691, issued to Ehinger extends beyond the guard rail which is hampered by the washer J and head of bolt 12 which prevents the blade from Cutting next to a wall surface. The adaptor in the Ehinger patent is a cylinder with a closed end that has a lug to hold a blade against spinning on the adaptor.
U.S. Pat. No. 1,883,392, issued to Moll, is directed to a power saw for making plural parallel cuts simultaneously. There is an arbor which threads on the shaft of a motor and spreaders to separate the blades. The particular power saw does not have a surrounding guard rail. Instead there is a hood to cover the blades, leaving the side of the blade exposed.
The present invention not only extends the blade beyond the guard rail, it also provides a saw blade compatable with the adaptor to preform cuts along a wall surface,